Synthetic drying oils from polyvinyl alcohol and method of production



Patented June 24, 1952 SYNTHETIC DRYING OILS FROM POLY- VINYL ALCOHOL PRODUCTION AND METHOD OF Glenwood L. Schertz, Wilmington, Del., assignor to Hercules Powder Company, Wilmington, DeL, a corporation of Delaware No Drawing. Application May 5, 1949, Serial No. 91,628

' Claims. {01. 260-23) This invention relates to synthetic drying oils and to a method for their production, and more particularly to the reaction product prepared from a polyvinyl alcohol and an unsaturated fatty acid and to methods for the production thereof.

This application is a continuation-in-part of my application Serial No. 676,106, filed June 11, 194.5, now abandoned.

In protective coating technology, one of the goals sought is the preparation of an oleoresinous coating composition having a drying speed approximating that of a lacquer, and which at the same time yields films of good durability and alkali and water resistance. The reaction prodnets of this invention, when dissolved in a suitable solvent, yield films which approximate these desired qualities very closely.

It has heretofore been proposed to form polymers of vinyl esters of unsaturated fatty acids. It has been found, however, that such vinyl esters do not form linear polymers but on the other hand form highly cross-linked compounds. Gelled, insoluble, infusible products usually result from attempted polymerization. In those cases wherein it is possible to isolate an ungelled polymer, it is found to be of low molecular weight, to possess poor drying characteristics and to provide films which do not possess the toughness of the films derived from natural drying oils.

In accordance with this invention it has been found that synthetic drying oils, of substantially improved drying characteristics as compared with natural drying oils, can be prepared by esterifying a polyvinyl alcohol of rather high molecular weight with an unsaturated fatty acid containing at least fourteen carbon atoms. The esterification reaction is carried out by heating the two materials in solution in a mutual solvent at a temperature of from about 150 C. to about 250 C.

The polyvinyl alcohols which may be used are those having an average molecular weight of from 6,000 to- 80,000, and preferably those alcohols having an average molecular weight of from 10,000 to 60,000 will be employed. Such polyvinyl alcohols which are partially but not entirely acetylated may be employed in accordance with this invention. Thus, polyvinyl alcohols defined as aforesaid which are acetylated to any extent up to and including 60% acetylation may be employed. By the term average molecular weight" it will be understood that there is meant an average molecular Weight on a number basis rather than on a weight basis. The term will formed.

castor oil fatty acids were then slowly added at be used in this sense throughout the specification and claims.

The reaction products are unsaturated fatty acid esters of polyvinyl alcohols. They have resinous characteristics and valuable and unique drying properties. They are of high molecular weight and are composed of linear molecules. Thus, they may properly be described as linear polymers rather than as cross-linked polymers. Coating compositions prepared by dissolving these new products in volatile solvents have a high drying speed, rapidly setting to tough hard films when applied to a surface at ordinary room temperature. The films so produced do not become brittle on aging and are exceptionally scuffresistant and give excellent performance in outdoor exposuretests.

The following examples are illustrative of the new drying oils and methods for the preparation thereof. In these examples all parts and percentages are by weight unlessotherwise specified.

Example I Eight hundred parts of phenol and 88 parts of polyvinyl alcohol were placed in a reaction vessel equipped with a stirrer, a thermometer, and a distilling arm which was so arranged that the phenol could be either refluxed or distilled out. The polyvinyl alcohol employed was a polymer having a. viscosity in 4% aqueous solutions at 20 C. of 5 cps. as determined using a Hoeppler viscosimeter. It had an average molecular weight of about 14,000. The phenol and polyvinyl alcohol were heated to C., at Which temperature a clear, homogeneous solution was Seven hundred parts of dehydrated a rate such that the solution showed no signs of turbidity. Simultaneously the temperature of the reaction mixture was slowly raised to C at which temperature the phenol began distilling. The addition of fatty acid and the removal by distillation of phenol were adjusted at rates such that the solution remained clear. At the end of 4 hours all of the fatty acid had been added, 750 parts of phenol and water had been recovered, and the reaction mixture had attained a temperature of 235 C. Esterification was continued for a further period of 216 hours at a temperature of 235 C. with a carbon dioxide sparge being employed. At this time, a total of 831 parts or" distillate containing phenol, water of esterification and any other volatile material had been recovered. The residue consisting of 760 parts of ester was next extracted 5 times with volumes of methyl alcohol equal to that of the ester.

This procedure yielded 358 parts of a methyl of 18 and a saponification number of 170.

The alcohol-insoluble portion was diluted with an equal weight of xylene and stabilized with 0.04% of guaiacol, based on the weight of the polyvinyl ester. After 0.05% cobalt drier (also based on the weight of the polyvinyl ester) had. been added, this solution dried cotton-free in 90'.

minutes and foil-free overnight when applied to a surface. I

Example II Forty-four parts of polyvinyl alcohol and 350 parts of oleic acid (U. S. P. grade) were kettled to form a reaction product using the procedure described in Example I and using 400 parts of phenol as a solvent. The polyvinyl alcohol employed was a polymer having a viscosity in 4% aqueous solution at 20 C. of 5 cps. as determined using a Hoeppler viscosimeter. age molecular weight of about 14,000. At the end of the reaction, 403 parts'of distillate containing phenol, water of esterification and other volatile material had been recovered. The residue after successive extraction with 5 volumes of methanol (based on the volume of residue) yielded 180 parts of ester having an acid number of and a saponificationnumber of 1'74.

A coating composition containing this reaction product diluted with. an equal weight of xylene and containing 0.04% of guaiacol, based upon the weight of the ester, and 0.05% of cobalt drier (also based upon the weight of the ester) set to a 4 hard film in 24 hours.

Example III a Eighty-eight parts of polyvinyl alcohol and 700 parts of linseed oil fatty acids were esterified as described in Example I, using 800 parts of phenol as the solvent. The polyvinyl alcohol employed was a polymer havinga viscosity in 4% aqueous solutions at 20 C. of 5 cps. as determined using a Hoeppler viscosimeter. It had anaverage molecular Weight of about 14,000. At the end of the esterification reaction, 788 parts of distillate containing phenol and water of esterification had been recovered. After successive extraction with 5 volumes of methanol equal to that of the crude ester, 395 parts of the finished ester was obtained having an acid number of 12.5 and a saponification'number'of 139. i

This low acid number ester was dilutedwith an equal volume of xylene and stabilized with 0.04% of guaiacol, based upon the weight of the ester. After the addition of 0.05% of cobalt drier (also based upon the weight of the ester) the coating composition produced dried cotton-free inv 50 minutes and foil-free in 5 hours.

Emmple IV Seventy-one parts of polyvinyl alcohol and 350 parts of linseed oil fatty acids were esterified as described in Example I using 400 parts of phenol as the solvent. The polyvinyl alcohol employed was a polymer having a viscosity in 4% aqueous solutions at 20 C. of 5 cps. as determined using a Hoeppler viscosimeter. It had an average molecular weight of about 14,000. An ester having an acid number of 125 was produced. One hundred parts of this viscous ester was extracted twice with methanol, to yield 65 parts of a reaction product having an acid number of 35.

A coating composition was prepared by diluting this product with an equal weight of .xylene and thereafter stabilizing with 0.04% of guaiacol.

It hadan aver- 4 After the addition of 0.05% of cobalt in the form of a drier, this coating composition dried foil-free in about 5 hours.

Example V Forty-four parts of polyvinyl alcohol and 350 parts of linseed oil fatty acids were esterified according to the procedure of Example I, using 400 parts 'of-creso'l (resin grade) as a solvent. The polyvinyl alcohol. employed was a polymer having a viscosity in 4% aqueous solutions at 20 C. of 5 cps. as determined using a Hoeppler viscosimeter. It had an average molecular Weight of about 14,000. After the esteriflcation reaction had been completed a reaction product having an acid number of 112 was produced, and 390 parts of distillate containing cresol, water of esterification and other volatile material had been recovered. Two hundred sixty-five parts of this high acid number ester were extracted 5 times with equal volumes of methanol to yield 129 parts of a meth-v yl alcohol-insoluble ester having an acid number of 11.

The ester was diluted with an equal weight of xylene and 0.04% of guaiacol added in order to 1 stabilize the mixture. A coating composition containing the diluted ester and 0.05% of cobalt in the form of a drier dried cotton-freein 50 minutes and foil-free in 6 hours.

Example VI Eighty-eight parts of polyvinyl alcohol and 700 parts of soybean oil fatty acids were'esterified" according to the procedure of Example "I, using 300 parts of phenol as a solvent. The polyvinyl alcohol employed was a polymer having a vis-' oosity in 4% aqueous solutions at 20 C. of 5 cps. as determined using a Hoeppler viscosimeter. It had an average molecular weight of about 14,000. After the esterification had been completed, a distillate containing 785 parts of A coating composition prepared by diluting,

the ester with an equal volume of xylene and 0.05% cobalt drier, based upon the weight of' ester, dried cotton-free in minutes and foilfree in 6 to 7 hours. At-temperatures of 98-100- C., this composition dried in 3 to 5 minutes.-

Example VII Forty-four parts of polyvinyl alcohol and 350' parts of linseed oil fatty acids were esterified as described in Example I using 4001parts .of phenol as solvent. The polyvinyl alcohol employed was a relatively high molecular weightpolymer having a viscosity in 4% aqueous solutions atv 20 C. of 55 cps. as determined by using a.

Hoeppler viscosimeter. It had an average mo-* lecular weight of about 52,000.

of methyl alcohol to yield a product similar in character to the purified esters of the foregoing" examples with the exception that it was much more viscous.

Example VIII A 25-gallon varnish was prepared by heating together partsof'a polyvinyl lineoleate (pre-" paredasdescribed in. Example IV) and. .95 parts;

of the pentaerythritol ester of rosin. The 2 in- The; resulting ester was extracted S'times with equal volumes" gredients were heated in an open kettle to 260 C. in to minutes. When a long string formed on the varnish paddle, the heat was removed and the varnish solids were thinned to 50% nonvolatile with Varsol (trade name for an aliphatic hydrocarbon fraction used for diluting varnishes). A cobalt drier, 0.05% based on the polyvinyl linoleate, was then added. This varnish had a viscosity of C to D on the Gardner- Holdt scale and dried foil-free in 3%, hours. The dried varnish film had the improved characteristics corresponding to those of the film from the polyvinyl ester alone.

It has been stated previously that the comparatively high molecular weight polyvinyl alcohols which are useful in accordance with this invention are those having an average molecular Weight of from 6,000 to 80,000, preferably those having an average molecular Weight of from 10,000 to 60,000. Polyvinyl alcohols of molecular weight 6,000 and 80,000 correspond with alcohols having about 130 and about 1800 hydroxyl groups per molecule. It will be evident, therefore, that the subject reaction products are quite highly polymeric in nature.

In the examples reference has been made to the viscosities in centipoises of 4% aqueous solutions at 20 C. of the polyvinyl alcohols employed using a I-Ioeppler viscosimeter. Such a measurement represents a practical means of ascertaining the approximate molecular weight of a particular polyvinyl alcohol. A polyvinyl alcohol having an average molecular weight of 14,000 will have an approximate viscosity determined as above-indicated of 5 centipoises, whereas a polyvinyl alcohol having an average molecular weight of 52,000 will have an approximate viscosity of 50-55 centipoises. The former type of polyvinyl alcohol may be referred to as a low viscosity type and the latter as a comparatively high viscosity type.

Polyvinyl alcohols are manufactured commercially by the hydrolysis of polyvinyl acetate. It is possible in the hydrolysis process to remove all or only part of the acetyl groups. As indicated previously, polyvinyl acetates which are only partially hydrolyzed may be used in carrying out the invention. Stated conversely, polyvinyl alcohols which are partially acetylated may be employed. Thus, the polyvinyl alcohols described in the foregoing paragraph which are acetylated to any extent up to and including 60% acetylaticn are useful in making the compositions of this invention. The polyvinyl alcohols which are substantially free of acetyl groups are, however, preferred. Although the invention is described in this specification with particular reference to such polyvinyl alcohols, it will be understood that the aforementioned partially acetylated alcohols are also operable and within the broad scope of the invention.

Any unsaturated fatty acid containing at least 14 carbon atoms, and preferably from 14 to 24 carbon atoms, may be esterified with the polyvinyl alcohol to produce the reaction products in accordance with this invention. The unsaturated fatty acid must contain at least one ethylene linkage and may contain two or more ethylene groups in any position in the hydrocarbon chain which unsaturation may or may not be present as a conjugated system of double bonds. Suitable acids for this purpose are myristoleic, palmitoleic, oleic, linoleic, linolenic, eleostearic, arachidonic, clupanodonic, licanic, lauroleic, gadoleic, erucic, etc. acids and their various isomers. Either the pure acids or mixtures of the acids may be used. A convenient source of these acids in the form of mixtures is obtained by the hydrolysis of nondrying, drying and semidrying oils. Oils, which on hydrolysis furnish suitable mixtures of unsaturated fatty acids, are dehydrated castor oil, linseed oil, tung oil, perilla oil, soybean oil, oiticica oil, poppyseed oil, fish oils, cottonseed oil, safilower oil, sunflower oil, etc. The fatty acids from these oils are for the most part acids which contain 18 carbon atoms. However, unsaturated acids containing less than 18 carbon atoms such as acids of 14 and 16 carbon atoms, and unsaturated acids containing more than 18 carbon atoms such as acids of 20 and 22 carbon atoms, as is the case of the fish oils, may be used. In the case of the fatty acids derived from tung oil and oiticica oil, due to their strong drying tendency, it is preferable to dilute them with less unsaturated fatty acids such as oleic acid, etc.

The proportion of fatty acid to polyvinyl a1- cohol may be varied as desired. Generally speaking, at least one mole of fatty acid is used per hydroxyl mole of polyvinyl alcohol. In the case of fatty acids obtained from naturally occurring drying oils, such as linseed oil fatty acids, the fatty acids are preferably used in an excess of from about 10% to about 25% in excess of molar proportions. However, in the case of some unsaturated fatty acids, it may be necessary to employ the fatty acid or acids in an excess up to about 50% excess of molar proportions.

As may be seen from the foregoing examples, the reaction products of this invention are prepared by first dissolving the polyvinyl alcohol in a mutual solvent for it and for the unsaturated fatty acid. In general, solution of the polyvinyl alcohol in the mutual solvent may be accomplished at any suitable temperature. Preferably a temperature within the range from about C. to about 200 C. is used. The polyvinyl alcohol will dissolve in the solvent such as phenol to form a clear, homogeneous, light-colored solution at C. in concentrations up to about 25% by weight. The unsaturated fatty acids are thereafter added slowly until in the previously clear solution there is produced a slight haze, which gradually disappears as esterification proceeds. There is an attendant gradual rise in the temperature of the reaction mixture as the mutual solvent and water of esterification distill off and as the fatty acids are added. However, as the reaction proceeds, the ester prodnot itself acts as a mutual solvent for the reactants and the mutual solvent originally employed may be gradually removed. This initial phase of the reaction generally requires about 4 hours, and completion of the esterification and removal of the mutual solvent require heating for a further period of from about 2 hours to about 5 hours at a temperature within the range of from about 150 C. to about 250 C. and preferably at about C. to about 235 C. The reaction mixture is preferably sparged with an inert gas, such as carbon dioxide, nitrogen, etc.. or a vacuum, in order to aid in the complete removal of the solvent. The resulting product will have an acid number which is dependant on the excess of fatty acid used and upon the extent' of reaction which has taken place.

Unreacted fatty acids can be removed from the reaction product by vacuum distillation, for example, at pressures of 1 to 2 mm. of mercury and at temperatures not in excess of 200 C.

An alternative procedure for removing unreactedfatty tacids is exemplified :by-the imethanol extraction process shown 1. in 1 the. examples. Broadly expressed, this procedure, involves contacting the. reaction productwitirla material which. isessentially' a solvent ,for the unreacted' 5 fatty .acid or acids. andnatv thesamextime. annon-r. solvent forthe ester. For this. purpose; instead: ofv the methyl alcoholdemployedrinthe examples, there maybe used suitably; any aliphatic alcohol; suchvas ethyl alcohoL: propyl-alcohoL: and iSO-r 1 propyl alcoho1.., By contactingtthe.relatively im: pure ester with such-a solvent; an: ester: having an acid:.number of.35 or less may ultimately-be produced.

Any material which is :a. solvent zforbothithe poylvinyl alcohol and: the-unsaturated fatty acids and which isvnonreactive with the: fatty-acids: andpolyvinyl alcohol under thereaction condi'-- tions may be employed in-carryingout the-reaction in accordance withthis-invention. Thus,: a 2 phenol "such as phenol, the cresols andth'e xylenols have also -been found useful in preparing these new reaction. products In-dissolvi-ng-the polyvinyl alcohol in thesolvent; solutionsconataming as high as about of polyvinyl alco- 25 hol may be employed inthe methodof-this invention. It is preferred, however,- to employ-solutions containing fromabout 10% toabout 15% of polyvinyl alcohol, because-such solutions have lower viscosity and are more -easi-ly-- handled. The recovery of phenol, cresol, or oth ersolvent material is generally of the order -of 90%. Such solvent can be --re-used-as recovered, butpreferably it is redistilled" Ibefore-re-use;

The "polyvinyl alcohol-unsaturated fatty 'acid esters prepared in accordance "with thisinvention'arenew compositions ofmatterwhich' are'ot particular value in coating compositions: These new reaction products are in the nature-of synthetic drying oils which set to tough; hard films 40 when used with cobalt drier, the;cobalt .drier being used in an amount such that there is present from 0.01% to 0.05% cobalt metaL-lo'ased on'. the. weight of the non-volatiles in solution. As these films age, they. dry harder but do, not become brittle. They are exceptionally. scuff resistant, will not lift under lacquer solvents when applied in thin: films, possess good 'water resistance, fair alkali resistance, and, produce vfilms having unusual depth of finish and. gloss, Films formed from these reaction products show-an unusual degreeof v."durability when subjected. to outdoor exposure tests. They were foundlto be equivalent in this respect to a 35 gallon-tong. oil oleoresinous varnish.

Coating compositions may be prepared from the reaction products of this invention by dissolving them in xylene, preferably-from about 25% to about 50% (based ontheweight of the nonvolatile materials present) or in some. other suitable solvent, such as toluene, theestersolvents as butyl acetate, hydrogenated naphthas, and the high solvency aliphatic hydrocarbons such as decalin and tetralin. In the preparation of a coating composition, itqis preferable -to add any'of the common antioxidants in the propor tions generally employed in the coating, composition art. Thus;=in place of the guaiacoldisclosed in the examples,- theresmaybeused hydroquinone,-- beta-naphthol, aniline; etc. Whenthe coating composition is ready for a use, i a: cobalt driermay; beadded to the extentthat there is' present'from 0.01 to 0.05%-,- cobalt: metal, based:- upon, the- Weight of the-nonvolatiles in solution:-

If desired, these new reaction products may be 11SEd Wilih resins, such as esterr um; pentaerythri tol esters of rosin,-,etc.=, to form-varn-ishes. These' new products are particularly valuable: for "the preparation of varnishessincetthey:dornot re,-

quire :long cooking andxprovide yarn-ishesh'aving: To prepare varnishes the reaction products of this invention 1 and-a; resin". are; merely heated 1 to 220-230 C. and;

rapid r drying properties.-

thinned: The long-"cooking atihighertempere aturesirequired by the," prior art:drying::oils::is.

eliminated;

These new reaction products'may also-,begusedsi to fortify natural drying oils-to improve. the

drying characteristics of the latter. Drying ioilsi and semidrying oils such as soybean oi1,.1inseed-1 oil,;.etc., may be. improved by; the addition; of varyingjamounts of thecpolyvinyl .alcohol esters. of this invention; These;admixtnres mayythen;

be: [processed further into 1 paints, varnishes; etch Thus, therpolwinyl alcohol esters 0f;th-is;in-

vention= are. advantageous in i that: theywcani be" used as protective-coatings withoutfurther :proce essi-ng, such as :kettlinginto :yarnishes; These. esters show unusual hold: out characteristics.

when used; as wood sealers in furniture finishes,

and. compare: f avorablyuwith' long .011 'oleoresinous 1 varnishes having an .oilflength ofiabout 35: gal-I ions in i outdoor exposures. used-in combination with resins touproduce-imiproved varnish'es. In addition, byrmeans ofithei reaction in accordance with this ,inventionitiis possible to convert fattyacids of :non-. or semi: drying oils such as oleic acid, etc.', into rapid dry:- ing oils.

What I claim and desire .to protect .by Letters:

Patent is:

1. A'water-insolublereaction product or apolyhydric alcohol and at \least. one mol perhydroxyl mol of the polyhydric alcohol of an ethylenically f unsaturated fatty acid material of the group consisting of-unsaturated fatty acids containing at least l carbonatoms and mixtures thereof, said polyh'ydric: alcohol being a member of the-group consisting of polyvinyl alcohols having. an averagemolecular weight offrom 6,000 to- ;000. andsuch polyvinyl alcohols which are acetyla-ted -to' any extent up to and including 60%.

2. The methodwhich comprises heating at-a temperaturewithinthe range of from Cato 250 0. a polyhydricalcohol and an ethylenically unsaturated fatty acid material ofthe group consisting of unsaturated fattyacids containing at least licarbon atoms and mixtures-thereof, in solution in a-mutual'solvent for-said alcohol and said unsaturated fatty-acid material,- fora period of time, sufiicient to produce --a reaction product of the alcohol and the unsaturated fatty acid l, poiyhydrie alcohol being'a member of the groupconsisting ot-polyvinyl alcohols having an avcrageumolecula-r weight'offrom: 6,0001ito r89;0.0);'and "such polyvinyl alcohols which; areryacetylatedr to. any'extent up-to and including, 60%;, said, ethylenically unsaturated fatty acid material beingsemployed in the: amount of-at least one molper hydroxyl mol otth'epolyhyd-ricalcohol;

3. The method:which:comprisestheatinghat a temperature withinwth'eyrangeiof IfI01'X1u1503C; to 25050. a polyhydricalcohol and;-an ,ethylenically unsaturated-fatty acidmaterial of 'the'group con sistinggof unsaturated fatty: acids containing. at

least": la jcarbon tatoms; andszmixtures thereof," in

solution in a: phenol; for; a period of time sufficien-t toiproduce aureactionzproductpf the a1co-- hol and the unsaturated fatty acid material, said They: may also -bei 9 polyhydrio alcohol being a member of the group consisting of polyvinyl alcohols having an average molecular weight of from 6,000 to 80,000 and such polyvinyl alcohols which are acetylated to any extent up to and including 60 said ethylenically unsaturated fatty acid material being employed in the amount of at least one mol per hydroxyl mol of the polyhydric alcohol.

4. The method which comprises heating at a temperature within the range of from 150 C. to 250 C. a polyhydric alcohol and an ethylenically unsaturated fatty acid material of the group consisting of unsaturated fatty acids containing at least 14 carbon atoms and mixtures thereof, in solution in phenol, for a period of time sufiicient to produce a reaction product of the alcohol and the unsaturated fatty acid material, said polyhydric alcohol being a member of the group consisting of polyvinyl alcohols having an average molecular weight of from 6,000 to 80,000 and such polyvinyl alcohols which are acetylated to any extent up to and including 60%, said ethylenically unsaturated fatty acid material being employed in the amount of at least one mol per hydroxyl mol of the polyhydric alcohol.

5. The method which comprises heating at a temperature Within the range of 150 C. to 250 C. a polyvinyl alcohol having an average molecular Weight of from 6,000 to 80,000 and a mixture of fatty acids obtained by the hydrolysis of linseed oil, in solution in phenol, for a period of time sulificient to produce a reaction product of the alcohol and the fatty acids, said mixture of fatty acids being employed in the amount of at least one mol per hydroxyl mol of the polyvinyl alcohol.

6. The method which comprises heating at a temperature within the range of 150 C. to 250 C. a polyvinyl alcohol having an average molecular weight of from 6,000 to 80,000 and a mixture of fatty acids obtained by the hydrolysis of dehydrated castor oil, in solution in phenol, for a period of time sufficient to produce a reaction product of the alcohol and the fatty acids, said mixture of fatty acids being employed in the amount of at least one mol per hydroxyl mol of the polyvinyl alcohol.

7. The method which comprises heating at a temperature Within the range of 150 C. to 250 C. a polyvinyl alcohol having an average molecular Weight of from 6,000 to 80,000 and a mixtureof fatty acids obtained by the hydrolysis of soybean oil, in solution in phenol, for a period of time sumcient to produce a reaction product of the alcohol and the fatty acids, said mixture of fatty acids being employed in the amount of at least one mol per hydroxyl mol of the polyvinyl alcohol.

8. The method which comprises heating at a temperature within the range of from. 150 C. to 250 C. a polyhydric alcohol and an ethylenically unsaturated fatty acid material of the group consisting of unsaturated fatty acids containing at least 14 carbon atoms and mixtures thereof, in solution in a mutual solvent for said alcohol and said unsaturated fatty acid material, for a period of time suflicient to produce a reaction product of the alcohol and the unsaturated fatty acid material, and thereafter extracting the resulting reaction product with a material which is a nonsolvent for said reaction product and a solvent for any unsaturated fatty acids associated with said reaction product to produce a purified reaction product of low acid value, said polyhydric alcohol being a member of the group consisting of polyvinyl alcohols having an average molecular weight of from 6,000 to 80,000 and such polyvinyl alco- 10 hols which are acetylated to any extent up to and including 60%, said ethylenically unsaturated fatty acid material being employed in the amount of at least one mol per hydroxyl mol'of the polyhydric alcohol.

9.-A coating composition comprising a reaction product of claim 1 and a solvent for the reaction product which is nonreactive with the other ingredients of the composition.

10. A coating composition comprising a reaction product of claim 1, an antioxidant, and a solvent for the reaction product which is nonreactive with the other ingredients of the composition.

11. A coating composition comprising a reaction product of claim 1, an antioxidant, a drier, and a solvent for the reaction product which is nonreactive with the other ingredients of the composition.

12. A. water-insoluble reaction product of a polyhydric alcohol and at least one mol per hydroxyl mol of the polyhydric alcohol of a mixture of ethylenically unsaturated fatty acids containingat least 14 carbon atoms, said polyhydric alcohol being a member of the group consisting of polyvinyl alcohols having an average molecular weight of from 6,000 to 80,000 and such polyvinyl alcohols which are acetylated to any extent up to and including 60%.

13. A. water-insoluble reaction product of a polyvinyl alcohol having an average molecular Weight of from 6,000 to 80,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of a mixture of ethylenically unsaturated fatty acids containing at least 14 carbon atoms.

14. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular weight of from 10,000 to 60,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of a mixture of ethylenically unsaturated fatty acids containing at least 14 carbon atoms.

15. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular weight of from 10,000 to 60,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of linseed oil acids.

16. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular weight of from 10,000 to 60,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of dehydrated castor oil acids.

17. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular weight of from 10,000 to 60,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of soybean oil acids. I

18. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular Weight of about 14,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of linseed oil acids.

19. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular weight of about 14,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of dehydrated castor oil acids.

20. A water-insoluble reaction product of a polyvinyl alcohol having an average molecular weight of about 14,000 and at least one mol per hydroxyl mol of the polyvinyl alcohol of soybean oil acids.

GLENWOOD L. SCI-IERTZ.

(References on following page) 

1. A WATER-INSOLUBLE REACTION PRODUCT OF A POLYHYDRIC ALCOHOL AND AT LEAST ONE MOL PER HYDROXYL MOL OF THE POLYHYDRIC ALCOHOL OF AN ETHYLENICALLY UNSATURATED FATTY ACID MATERIAL OF THE GROUP CONSISTING OF UNSATURATED FATTY ACIDS CONTAINING AT LEAST 14 CARBON ATOMS AND MIXTURES THEREOF, SAID POLYHYDRIC ALCOHOL BEING A MEMBER OF THE GROUP CONSISTING OF POLYVINYL ALCOHOLS HAVING AN AVERAGE MOLECULAR WEIGHT OF FROM 6,000 TO 80,000 AND SUCH POLYVINYL ALCOHOLS WHICH ARE ACETYLATED TO ANY EXTENT UP TO AND INCLUDING 60% 